Tire mold



referate nee. s, resa.

, nier-a far snr A JOHN S. MCCLURG, F NEW YORK, lll". Y., ASSGNQR, BY MESNE ASSIGNMENTS, T0

CARLISLE TIRE CORPORATION, .A CORPORATION OF DEIJAWARE.

TIRE MGLD.

State of New York, have invented'certainv new and useful improvements in Tire vMolds, of which the following is a speciica tion.

My invention relates to tire molds or" the type in which pneumatic tire casings are cured or vulcanized and has for its object the provision of a simple and novel construction in which the use of the customary air bag for infiating the casing in the mold is l5 obviated. Other more specific objects of my invention will appearv from the description Ihereinafter and the features of novelty will be pointed out in the appended claims.

In the accompanying drawings, which illustrate an example or' myinvention without defining-its limits, Fig. 1 `is a diametrical cross section of the mold and Fig. 2 is a fragmentary cross section on an enlarged scale.

The mold may be lof any conventional form and as shown comprises the sections 5 'provided with complemental recesses 6 conforming throughout to all parts of the side walls and tread of the casing 7 and arranged, when operatively combined, to enclose and 50 snugly fit the same, said recesses having* continuing surfaces 8 which define the outer form of the customary beads 9. The sections 5 are arranged to it together at 10, preferably with an overlap, so as to provide an S5 eliicient-joint between said sections, and in :addition are provided with the usual members 11 whereby said sections are securely fastened together in their co-operative relation. Annuler flanges `12 comprising ineo tegral parts of each section 5 are located at the inner portion thereof and project toward each other as shown in the drawings. The mold further includes a metal bull-ring 13 which overlaps and lies in surface engageae ment withthe outer surfaces of said anges 12, said ring being formed 'with an annular, relatively reduced rib 14 arranged to t be tween the ianges 12as shown in the `drawn ings. The rib 14 is continued in 'the forni 5o of an inner member 15 projecting laterally in 'opposite directions to forni annularshoulders 15, which overlap and engage-the,

. flanges 12 on the inside, said member 15, in 'its preferred form, heilig further formed in with annular shoulders 16 deining the `inner thereof, firmly against face o Application led December 24, 1919. Serial No. 347,225

forni of the beads 9 and engaging the saine, as shown'. in F ig. 2; when the parts are as sembied the surfaces 8 and 16 are spaced apart to forni annular recesses for the ac\ connnodation of said beads 9. A. valve stem 17 oi anysuitable construction extends through a radial passage formed in the bullring 13, audits components, the rib 14- and inner member 15, and is secured therein in any convenient 'manner as by soldering; the valve eterni.- 17| projects inwardly beyond the bull-ring 13 and'isarranged for detachknown way. n

in utilizing the mold the carcass is placed in the one Section5 and the bull-ring 13 with able connection with an air pump in the well its component parte is properly combined with said section and then theother section is connected with the first section and with the bull-ring.l After this has been done suit'- able pressure is applied to themold to force the sections 5 and the bull-ring 13 into firm engagement with each other;"tlie parte -are then .securely fastened together in `this relation in any Well known wayas by bolting. By the above operations the uncured beads 9 are compressed in the annular'recesses and thus act in the nature oi gaskets whereby the joints or connections between the sections 5 and the bul1ring 18 are rendered air tight; the inside of the carcass plus thebull-ring thus becomes an absolutely air tight chainu ber. Air is then introduced through the valve stem 17 by means of a suitable air pump or the like to distend the carcass or casing 7 into firm, even engagement with the inner surface oi" the incid aiter which the latter is ready to be placed in the vulcanizer in the regular way. The air pressure within the casing, no matter how high within the limits o'i the device it niay'frise, tends to force the member 15 of the bull that .is to say, the annular shoulders i5? y of the danges 12 of the mold and thereby' prevents the possibility of any escape of air at thesel points; if, however, for any reason, 'air should work its way between the casing and the member 15, der pressure, will bring about a conipression of the rubber of the beads 9 and thus jane it againstthnnular shoulders ldand into' *any exit crevice which may tend to 'for-iii.

nchen occurrence, which ordinariiy *would prove disastrous to the eiicieneyof the mold,

the fact that such air is unring 13,

-iio

' in the present construction only still Jfurther assure the air tightness y As the usefulness oaf Serves to thereof. the air-bags used in Athe vulcanization of'ti-re casings is generally I sure directly to the casing,

productiono'f said tire casings.

material 1s possible Wtih the present inven4 tion, thus materially reducing the cost of At the same time the absence of an vair bag does away With objections resulting from its use, such as pinching of the bag and the consequent effect upon trie interior surface of the casing; furthermore, by applying the air presthe latter is positively'distended vinto proper engagement fwith the mold and an'interiorsurface of maximum uniformity is produced..

Various changes inthe specific form shown and described may be made Within the scope of the claims Without departing from the spirit of my invention.

l claim:

1. A mold for vulcanizing tire casings comprising complemental sections arranged to contain the casing, annular flanges forming part of said sections and projecting toward each other and presenting inside of the mold an annular seat for a co-operating annular member; an annular member fitted between said flanges and confining the beads of; the casing under pressure whereby the interior of said casing is converted into an air-tight chamber, said member being protesta/rae vided with annular "shoulders extending across and adapted to engage the seat on the said flanges on the inside and arranged to be forced into contact with the same by the pressure fluid Within the casing and under corresponding pressure to preserve the air tightness of said chamber, and means where- -by pressure fluid isintroduced into the latter.

2. A mold oryulcanizing tire easing comprising complemental sections arranged to contain the casing, annular flanges forming part of said sections and projecting toward each other and presenting inside of the mold an annular seat for a co-operating annular member; an annular member fitted between said fianges and confining the beads of the casing under pressure lwhereby the interior of said casing is converted into an air-tight chamber, said member being provided With annular shoulders adapted, in conjunction with said flanges, to define spaces into which said beadsare forced, additional annular shoulders on said member extending across and adapted to engagethe seataon the said flanges on the inside and arranged to be forcedinto contact with thesame by the 7. 'pressure fluid .within the'casing and under corresponding pressure to preserve the air tightness of said chamber, and a valve stem carried by said annular member whereby pressure fluid is introduced into said chamber., l

In testimony whereof l have .hereunto set my hand`4 JOHN MCCLURG. 

